Materials Science Forum, Vol.512, 383-388, 2006
Bonding of various metals using Ag metallo-organic nanoparticles - A novel bonding process using Ag metallo-organic nanoparticles
We propose a novel bonding process using Ag metallo-organic nanoparticles, of which the average particle size is around 11 nm. In this paper, Al, Ti, Ni, Cu, Ag and Au disc joints were made using the Ag metallo-organic nanoparticles in order to investigate the bondability of the various metals. These joints are evaluated based on measurement of the shear strength, and the observation of the fracture surfaces and the cross-sectional microstructures. The shear strength of the various metal joints increased in the following order: Al, Ti, Ni, Cu, Ag and Au. This corresponds to the order of the standard-free energy value of the oxide formation for each metal. In particular, while the strengths of the Cu, Ag and Au joints, in which the oxides can be reduced by carbon, were the same level, those of the Al and Ti joints, of which the oxides were more stable than carbon oxides, were extremely low. This result suggests that the carbon atoms or organic elements generated by the decomposition of the organic shell of the Ag metallo-organic nanoparticles may play a role in deoxidizing the oxide film on the metal surface. This can promote chemical bonding between the Ag nanoparticles and metals at low temperatures.